/*
 * Copyright (C) 2008 ZXing authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.google.zxing.client.android;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.View;

import com.google.zxing.ResultPoint;
import com.google.zxing.client.android.camera.CameraManager;
import com.zzh.lib.qr.R;

import java.util.ArrayList;
import java.util.List;

/**
 * This view is overlaid on top of the camera preview. It adds the viewfinder rectangle and partial
 * transparency outside it, as well as the laser scanner animation and result points.
 *
 * @author dswitkin@google.com (Daniel Switkin)
 */
public final class ViewfinderView extends View {

    private static final int[] SCANNER_ALPHA = {0, 64, 128, 192, 255, 192, 128, 64};
    private static final long ANIMATION_DELAY = 80L;
    private static final int CURRENT_POINT_OPACITY = 0xA0;
    private static final int MAX_RESULT_POINTS = 20;
    private static final int POINT_SIZE = 6;

    private CameraManager cameraManager;
    private final Paint paint;
    private Bitmap resultBitmap;
    private final int maskColor;
    private final int resultColor;
    private final int laserColor;
    private final int borderColor;
    private final int resultPointColor;
    private int scannerAlpha;
    private List<ResultPoint> possibleResultPoints;
    private List<ResultPoint> lastPossibleResultPoints;

    private int laserFrameCornerWidth = 6;
    private int laserFrameCornerLength = 50;
    private String drawText = "将二维码/条码放入框内，即可自动扫描";//提示文字
    private int drawTextSize = 30;//提示文字大小
    private int drawTextColor = Color.WHITE;//提示文字颜色
    private boolean drawTextGravityBottom = true;//提示文字位置
    private int drawTextMargin = 60;//提示文字与扫描框距离
    private int animationDelay = 0;

    // This constructor is used when the class is built from an XML resource.
    public ViewfinderView(Context context, AttributeSet attrs) {
        super(context, attrs);

        // Initialize these once for performance rather than calling them every time in onDraw().
        paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        Resources resources = getResources();
        maskColor = resources.getColor(R.color.viewfinder_mask);
        resultColor = resources.getColor(R.color.result_view);
        laserColor = resources.getColor(R.color.viewfinder_laser);
        borderColor = resources.getColor(R.color.scanborder_color);
        resultPointColor = resources.getColor(R.color.possible_result_points);
        scannerAlpha = 0;
        possibleResultPoints = new ArrayList<>(5);
        lastPossibleResultPoints = null;
    }

    public void setCameraManager(CameraManager cameraManager) {
        this.cameraManager = cameraManager;
    }

    @SuppressLint("DrawAllocation")
    @Override
    public void onDraw(Canvas canvas) {
        if (cameraManager == null) {
            return; // not ready yet, early draw before done configuring
        }
        Rect frame = cameraManager.getFramingRect();
        Rect previewFrame = cameraManager.getFramingRectInPreview();
        if (frame == null || previewFrame == null) {
            return;
        }
        int width = canvas.getWidth();
        int height = canvas.getHeight();

        // Draw the exterior (i.e. outside the framing rect) darkened
        paint.setColor(resultBitmap != null ? resultColor : maskColor);
        canvas.drawRect(0, 0, width, frame.top, paint);
        canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);
        canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1, paint);
        canvas.drawRect(0, frame.bottom + 1, width, height, paint);

        if (resultBitmap != null) {
            // Draw the opaque result bitmap over the scanning rectangle
            paint.setAlpha(CURRENT_POINT_OPACITY);
            canvas.drawBitmap(resultBitmap, null, frame, paint);
        } else {
            drawFrame(canvas, frame);//绘制扫描框
            drawFrameCorner(canvas, frame);//绘制扫描框4角
            drawText(canvas, frame);// 画扫描框下面的字
            drawLaserLine(canvas, frame);//绘制扫描线
            drawResultPoint(canvas, frame, previewFrame);//绘制扫描点标记
        }
        // Draw a red "laser scanner" line through the middle to show decoding is active
     /* paint.setColor(laserColor);
      paint.setAlpha(SCANNER_ALPHA[scannerAlpha]);
      scannerAlpha = (scannerAlpha + 1) % SCANNER_ALPHA.length;
      int middle = frame.height() / 2 + frame.top;
      canvas.drawRect(frame.left + 2, middle - 1, frame.right - 1, middle + 2, paint);

      float scaleX = frame.width() / (float) previewFrame.width();
      float scaleY = frame.height() / (float) previewFrame.height();

      List<ResultPoint> currentPossible = possibleResultPoints;
      List<ResultPoint> currentLast = lastPossibleResultPoints;
      int frameLeft = frame.left;
      int frameTop = frame.top;
      if (currentPossible.isEmpty()) {
        lastPossibleResultPoints = null;
      } else {
        possibleResultPoints = new ArrayList<>(5);
        lastPossibleResultPoints = currentPossible;
        paint.setAlpha(CURRENT_POINT_OPACITY);
        paint.setColor(resultPointColor);
        synchronized (currentPossible) {
          for (ResultPoint point : currentPossible) {
            canvas.drawCircle(frameLeft + (int) (point.getX() * scaleX),
                              frameTop + (int) (point.getY() * scaleY),
                              POINT_SIZE, paint);
          }
        }
      }
      if (currentLast != null) {
        paint.setAlpha(CURRENT_POINT_OPACITY / 2);
        paint.setColor(resultPointColor);
        synchronized (currentLast) {
          float radius = POINT_SIZE / 2.0f;
          for (ResultPoint point : currentLast) {
            canvas.drawCircle(frameLeft + (int) (point.getX() * scaleX),
                              frameTop + (int) (point.getY() * scaleY),
                              radius, paint);
          }
        }
      }

      // Request another update at the animation interval, but only repaint the laser line,
      // not the entire viewfinder mask.
      postInvalidateDelayed(ANIMATION_DELAY,
                            frame.left - POINT_SIZE,
                            frame.top - POINT_SIZE,
                            frame.right + POINT_SIZE,
                            frame.bottom + POINT_SIZE);
    }*/
    }

    /**
     * 画扫描框
     *
     * @param canvas
     * @param frame
     */
    private void drawFrame(Canvas canvas, Rect frame) {
        int width = canvas.getWidth();
        int height = canvas.getHeight();
        paint.setColor(resultBitmap != null ? resultColor : maskColor);
        canvas.drawRect(0, 0, width, frame.top, paint);
        canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);
        canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1, paint);
        canvas.drawRect(0, frame.bottom + 1, width, height, paint);
    }

    private void drawResultPoint(Canvas canvas, Rect frame, Rect previewFrame) {
        float scaleX = frame.width() / (float) previewFrame.width();
        float scaleY = frame.height() / (float) previewFrame.height();

        List<ResultPoint> currentPossible = possibleResultPoints;
        List<ResultPoint> currentLast = lastPossibleResultPoints;
        int frameLeft = frame.left;
        int frameTop = frame.top;
        if (currentPossible.isEmpty()) {
            lastPossibleResultPoints = null;
        } else {
            possibleResultPoints = new ArrayList<>(5);
            lastPossibleResultPoints = currentPossible;
            paint.setAlpha(CURRENT_POINT_OPACITY);
            paint.setColor(resultPointColor);
            synchronized (currentPossible) {
                for (ResultPoint point : currentPossible) {
                    canvas.drawCircle(frameLeft + (int) (point.getX() * scaleX),
                            frameTop + (int) (point.getY() * scaleY),
                            POINT_SIZE, paint);
                }
            }
        }
        if (currentLast != null) {
            paint.setAlpha(CURRENT_POINT_OPACITY / 2);
            paint.setColor(resultPointColor);
            synchronized (currentLast) {
                float radius = POINT_SIZE / 2.0f;
                for (ResultPoint point : currentLast) {
                    canvas.drawCircle(frameLeft + (int) (point.getX() * scaleX),
                            frameTop + (int) (point.getY() * scaleY),
                            radius, paint);
                }
            }
        }
    }

    ;

    /**
     * 画扫描线
     *
     * @param canvas
     * @param frame
     */
    private void drawLaserLine(Canvas canvas, Rect frame) {
        paint.setColor(laserColor);
        paint.setAlpha(SCANNER_ALPHA[scannerAlpha]);
        scannerAlpha = (scannerAlpha + 1) % SCANNER_ALPHA.length;
        int middle = frame.height() / 2 + frame.top;
        canvas.drawRect(frame.left + 2, middle - 1, frame.right - 1,
                middle + 2, paint);
//        paint.setStyle(Paint.Style.FILL);
//        paint.setColor(laserColor);// 设置扫描线颜色
//        canvas.drawRect(frame.left+2, laserLineTop, frame.right-2, laserLineTop + laserLineHeight, paint);

    }

    /**
     * 绘制提示文字
     *
     * @param canvas
     * @param frame
     */
    private void drawText(Canvas canvas, Rect frame) {
        int width = canvas.getWidth();
        paint.setColor(drawTextColor);
        paint.setTextSize(drawTextSize);
        final float textWidth = paint.measureText(drawText);//取出文字宽度
        float x = (width - textWidth) / 2;//文字开始位置
        //根据 drawTextGravityBottom 文字在扫描框上方还是下文，默认下方
        float y = drawTextGravityBottom ? frame.bottom + drawTextMargin : frame.top - drawTextMargin;
        canvas.drawText(drawText, x, y, paint);
    }

    private void drawFrameCorner(Canvas canvas, Rect frame) {
        paint.setColor(borderColor);
        canvas.drawRect(frame.left, frame.top, frame.left + laserFrameCornerWidth,
                frame.top + laserFrameCornerLength, paint);
        canvas.drawRect(frame.left, frame.top, frame.left + laserFrameCornerLength, frame.top
                + laserFrameCornerWidth, paint);
        canvas.drawRect(frame.right - laserFrameCornerWidth, frame.top, frame.right,
                frame.top + laserFrameCornerLength, paint);
        canvas.drawRect(frame.right - laserFrameCornerLength, frame.top, frame.right, frame.top
                + laserFrameCornerWidth, paint);
        canvas.drawRect(frame.left, frame.bottom - laserFrameCornerLength, frame.left
                + laserFrameCornerWidth, frame.bottom, paint);
        canvas.drawRect(frame.left, frame.bottom - laserFrameCornerWidth,
                frame.left + laserFrameCornerLength, frame.bottom, paint);
        canvas.drawRect(frame.right - laserFrameCornerWidth, frame.bottom - laserFrameCornerLength,
                frame.right, frame.bottom, paint);
        canvas.drawRect(frame.right - laserFrameCornerLength, frame.bottom - laserFrameCornerWidth,
                frame.right, frame.bottom, paint);
    }

    public void drawViewfinder() {
        Bitmap resultBitmap = this.resultBitmap;
        this.resultBitmap = null;
        if (resultBitmap != null) {
            resultBitmap.recycle();
        }
        invalidate();
    }

    /**
     * Draw a bitmap with the result points highlighted instead of the live scanning display.
     *
     * @param barcode An image of the decoded barcode.
     */
    public void drawResultBitmap(Bitmap barcode) {
        resultBitmap = barcode;
        invalidate();
    }

    public void addPossibleResultPoint(ResultPoint point) {
        List<ResultPoint> points = possibleResultPoints;
        synchronized (points) {
            points.add(point);
            int size = points.size();
            if (size > MAX_RESULT_POINTS) {
                // trim it
                points.subList(0, size - MAX_RESULT_POINTS / 2).clear();
            }
        }
    }

}
